Methods, systems, and devices for write operation techniques for memory systems are described. In some memory systems, write operations performed on target memory cells of the memory device may disturb logic states stored by one or more adjacent memory cells. Such disturbances may cause reductions in read margins when accessing one or more memory cells, or may cause a loss of data in one or more memory cells. The described techniques may reduce aspects of logic state degradation by supporting operational modes where a host device, a memory device, or both, refrains from writing information to a region of a memory array, or inhibits write commands associated with write operations on a region of a memory array.

A memory system, a memory controller and an operating method are disclosed. A first area, a second area included in the first area, and a third area are set. An area to which target data is to be written is determined to the first area or the third area. When the target data is written to the first area, the target data is preferentially written to the second area. The number of data bits stored per memory cell in the first area is less than the number of data bits stored per memory cell in the third area. As a consequence, it is possible to secure storage capacity of the memory system to at least a set reference while securing data write performance of the memory system recognized by a host to at least a set reference.

Disclosed in some examples are methods, systems, devices, and machine-readable mediums that provide for techniques for scrambling and/or updating meta-data that enable an efficient internal copyback operation. In some examples, improved data distribution techniques decouple the scrambling key from a physical address to allow for copyback operations while maintaining data distribution requirements across a memory device. The controller may generate a seed value that is used by a scrambling algorithm to scramble the host-data and meta-data prior to the data being written. The seed value is then encoded and written to the page with encoded versions of the scrambled user data and meta-data—the random seed is written without scrambling the random seed.

A memory sub-system configured to dynamically determine input/output sizes of write commands based on a media physical layout of a memory sub-system. The memory sub-system can identify, dynamically in response to write commands being selected for execution in media units of the memory sub-system, a portion of a media layout that maps from logical addresses identified by the write commands in the logical address space to physical addresses of memory units in the media units. Based on the media layout, an input/output size for a next write command is identified and transmitted to the host system in a response. The host system generates the next write command and configures the amount of data to be written through the next write command based on based on the input/output size identified in the response.

A memory system includes a nonvolatile memory which comprises a plurality of memory cells capable of storing 4-bit data represented by first to fourth bits by sixteen threshold regions, and a memory controller configured to cause the nonvolatile memory to execute a first program for writing data of the first bit, the second bit, and the fourth bit and then causes the nonvolatile memory to execute a second program for writing data of the third bit. In fifteen boundaries existing between adjacent threshold regions among the first to sixteenth threshold regions, a maximum value of the number of first boundaries used for determining a value of the data of the first bit, the number of second boundaries used for determining a value of the data of the second bit, the number of third boundaries used for determining a value of the data of the third bit.

A method of programming a nonvolatile memory device includes performing a single-pulse program operation in a program loop, determining whether a condition is satisfied in the a program loop, and performing a multi-pulse program operation in a next program loop when the condition is satisfied. The single-pulse program operation includes applying a first program pulse and applying plural verification pulses, the multi-pulse program operation includes applying a second program pulse, applying a third program pulse, and applying plural verification pulses, and each of the second program pulse and the third program pulse has a level lower than a level of the first program pulse.

Some embodiments include apparatuses and methods of using the apparatuses. One of the apparatuses includes a substrate, a first deck including first memory cell strings located over the substrate, a second deck including second memory cell strings and located over the first deck, first data lines located between the first and second decks and coupled to the first memory cell strings, second data lines located over the second deck and coupled to the second memory cell strings, and first and second circuitries. The first and second data lines extending in a direction from a first portion of the substrate to a second portion of the substrate. The first buffer circuitry is located in the first portion of the substrate under the first memory cell strings of the first deck and coupled to the first data lines. The second buffer circuitry is located in the second portion of the substrate under the first memory cell strings of the first deck and coupled to the second data lines.

The present disclosure provides a method of data protection for a three-dimensional NAND memory. The method includes programming a memory cell of the 3D NAND memory according to programming data; and backing up a portion of the programming data associated with the memory cell in response to a program loop count (PLC) that is larger than a threshold value, where the PLC tracks a repeated number of the programming of the memory cell. A previous PLC can be set as the threshold value, where the previous PLC was used by a previous programming operation and was collected after the memory cell was programmed successfully to a previous target logic state.

A controller includes memory and a microcontroller coupled to the memory. The memory is configured to store a list of entries of data in Flash memory coupled to the controller. The microcontroller is configured to periodically update the list of entries based on data programmed into the Flash memory, and check the list of entries upon reading data from the Flash memory.

Numerous embodiments are disclosed for accessing redundant non-volatile memory cells in place of one or more rows or columns containing one or more faulty non-volatile memory cells during a program, erase, read, or neural read operation in an analog neural memory system used in a deep learning artificial neural network.